Extraction apparatus



July 2, 1935. c. RASCHER ET AL EXTRACTION APPARATUS Filed July 20, 1954 "INVENTORSI CHARLES RASCHER 8\ I MAX F BETZOLD 5 ATT'Y extraction tube'including means for readily re- 1 At t further PatentedJuly 2 1935 I V l 7 NITED sures PATENT omen V I 2306,5 13 I I EX'rRAo'rIoN ArPARA'rIis Charles Rascher andfMax Betzold, Chicagot 111., assignors' to -Rancher 8; Betzold, IncL, Chi- 'cago Ill., a corporationof-Illinois p I et ueati nr u y 20,1934, Serial No. 73 ,226

r 1 -17 Claims, (01. zit- 259) The present invention relates to extraction ap.- fi hazard is greatly reduced if notpractically p ratus and has for one o its objects the provision eliminated. 1 r p Q. of means whereby one can better control the Another object of this invention istoprovide a solvent during the extracting operation and;.pre.- condenser and extraction apparatus which will vent the contamination oi the same so that'the not sweat. Thisi V y important the '5 best. results may be obtained; that the-moisture thus, formed may seep into the 4 Another object of this i e ti is t provide solvent or into the extraction tube or fall int o an improved extraction apparatus of thersoxhlet am w ng the various Parts Of th 7 type, comprisingaliquid receiving flask for the same as when placing the' flask and extractor in lo solvent, an extraction tube and a condenser. I In p a v a ion w h other o ov n this typeof apparatus the material to be treated em from, their, operative positions. Water in 1 is placed in the extraction tube and the solvent t e t actormay cause ma m be td $S9 is placed in the flask. Heat is appliedto the flask out of the material which was'not intended to be to. vaporize the solvent and 'thevapo'rs fromthe Qlved out; Ort w n ay form dS hm 1;. solvent enter the extraction tube where they are c mp u ds Sin t tests r o med condensed and fall to the bottom of the tube; the with appa a s such as t i q i e e weighing solventthereafterdissolving outpart of the mateof the residual pa ts n'th e ra t a d n he rial and carrying the same back to the flask when flaskfihe presence of'moisture W ic W disturb the'liquidsolvent is siphoned into the flask. inthe the expected results,is very undesirable andit is 20 manner which will be set forth later andtwhioh' our obiechto eliminate thi possibility i 90 1- 2 is well understood in. the art to. .which this intamination by providing an improvecljcondenser. vention pertains. 1- Another object of this invention is; to provide Another object of this invention is to provide an means for indicating when and at what rate the improved liquid seal between the flask and the oO i l is flOWing throughihepondgnself: bject of this invention is to moving the liquid forming the sealwhenand it provide means, f pp e, conden er. desired, as for instance when one desires to rewhile the material being treated is being-remove the contents of the flask. In the usual type movedfrom or being placed in the extraction of apparatus of this nature, one. tips the flask to tube, withflu v interrupting the flow of c in remove the contents of theflask and 'sir nultajfiuidxthrough t c n The pp h 3;) neously remove the liquid forming the seal. means-also preferably acts to hold the flexible Separate receptacles are provided for these and rubber tubes over the glass inlet and Outlet 2 ii oneis not careful some of the mercury,- which duits of" the condenser. This means alsqmalses is usually'used as the sealing fluid, may fall into it unnecessary to remove the flexible outlet tube the receptacle for the contents of the flask with from thedrain pipe and enables the condenser-to 3 the result that the contents of the flask .is conk function evenewhen removed from the extraction tamina'ted. With-our apparatus themercury, seal tube'as will:bejbrought out more fully inthe may be quickly removedbefore tilting. the flask description-L it I 1 and then the contents of the flask poured intoa otner. objects of this invention will appear 4?: suitable receptacle. 1 as the description of the same proceeds, the novel 40 Another object of this invention is to'r'educethe -ieatures,.-;arrangements and combinations being fire hazard in apparatus of this nature. Asolclearly Set forth Specification d. h p vent which is inflammable is generally usedand claims there-unto ap in the usual type of liquid fseal, some of theicon- In the-drawin p densed solvent vapors are brought into contact -'..Fig. lxisafront elevation of one embodiment of r with the liquid sealing materialand there is a our invention;

possibility of this being carried to an exposed Fig. 2-isacross-,section of the lower partof the 1 point'of the apparatus.- If this occurs and there device shownzin Fig. 1. taken in a vertioalplane is an open flame or spark in the "vicinityian exthroughthecenter of the apparatus and parallel plosion ortire is apt to result. The solvent. will to the sheet .onwhich the drawing appears; 5Q

collect on the top of the mercury and when the Fig.3 is a cross-section similar vto Fig. 2 showi V extraction tube is removed. this solvent is naturally lng the.upp er;part of theapparatus; and exposed. When the extractiontube is againyput Fig.4 isa cross-section taken substantially in place some of this solvent is on exposed poralong the line l-Aof Fig.3.

5. tions of the mercury. With our apparatus this The embodimentshown comprises'a-flaskiil in which the solvent is placed, and II is an extraction tube of the Soxhlet type, the former resting on the heating plate I2 and the latter being supported in any desired manner as by a clamp on a clamp stand such as is usually used in laboratory work. A cooling fluid such as water is supplied to the condenser I3 of the apparatus from some convenientsource suchasthe water pipe [4, extending in a substantially horizontal position above the apparatus, through the rubber inlet tube 15. The cooling water leaves the condenser through the rubber outlet tube l6.

The extraction tube comprises tube I 'I- the bottom of which is rounded and has an inlet port J8 and an outlet port IS. The bottom of the tube has a vapor conduit 20 fused to it in alignment with the axis of the tube. Thelower end of this conduit is flared outwardly and downwardly to form the skirt 2|, and a second skirt. 22- is insed conduit 20 as is clearly indicated in Fig. 2.

r The flask 'lllwhich receives'the'solvent for-the extraction process has afsubstantially cylindrical mouth portion 25, on theexteri'orcircumi'erem tial portion of which'the're is formed a trough 26,

the upper edge 21 of the outer wall thereof being below the lip 28 of the flask. Mercury 26"is placed. in' 'this trough and acts as a connecting seal betweenthe flask andextraction tube when the outer skirt is lowered intothemercury as is illustrated in Fig. 2.-' The vapors-formed when the solvent is heated are therefore constrained to m'ove' upwardly through the conduits and '23into theextractor 'H where, after being condensed by their contact with the condenser, the liquid solvent falls to'the bottom of the tube I'l onto the material therein. This solvent collects in thebottom of the tube and remains there until the level of the same is high enough to reach the top 29 of the siphon tube 24 atwhich time the siphon becomes operative to" siphon-the solvent and dissolvedmatter back in to thefiask-io. This process is carried on'as long as desired or necessary, with the solvent periodically siphoning back into the flask-where it is re-vaporized and sent again to the extraction chamber.

In the bottom'of the extraction chamber is placed a paper thimble 30 or like-receptacle for the material to be treated, and this contains a known amount'of material to be treated by the solvent. The-solvent dissolves out part0! this material and carries it down into the flask I0 when the siphoning takes place...

When, for any reason, it isdesired'to separate the extraction tube and flask, the" tube I'I' is generally moved upward awayfrom the flask and the flask is then moved laterally away fr'om' its position beneath the extractiontube. :Any means may be providedfor permitting this-separation if and when desired. It-is during' thiss'eparation that moisture formed on theexterior of the ex.- traction tube can fall in'tothe flask, but with our apparatus this will not result due. tothe fact that the condenser we provide prevents .the formation of such moisture on the extraction tubef "Itiis also at this time that any-" 0f the solvent which sake of clearness. slight depressions 42 in the, upper lipportion end of thecondenser tube. vent vapors to rise about the sides of the conmay have collected on the mercury is exposed and may ignite as previously explained.

Before or after raising the tube 51, the inercury can be removed from the trough 25 by means forming an important part of this invention, so that the flask can be emptied readily. This means comprises an integral outlet tube 32 extending downwardly and outwardly from the bottom of the troughpthe same beingprovided with a stopper formed of a solid glass rod 33 about which has been placed a short length of rubber tubing 34 which snugly fits the glass rod. When thisstopp er is removed the mercury will drain out of the trough and a suitable receptacle can beprov'ided for receiving the same. Thus there is-no danger of spilling the mercury into the receptacle for the solvent such as is always present in using extraction apparatus such as that described as prior art.

When the flask is first heated and the hot vapors rise into the conduits 20 and23, some of the vapors condense on the still cold 'walls of the conduits and drain back into the flask l9, moving along the inner wall of the inner skirt 22 in so doing. If it were not for the skirt 22 the condensed vapors so formed would drain back along the skirt 2| into the mercury. This, as previously explained, is undesirable due to theme hazard.

In the top of the extraction tube we place our improved condenser and this is shown particularly in Fig. 3. Itcomprises a hollow tube 35 having a rounded bottom 36 and a concave top 31, the peripheral edge of which is provided with a downwardly extending lip 31'. A conduit 38 arranged centrally of the tube 'is fused to and extends through the top 3land has the outside extension 39 arranged within the lower end of the tube 15, thelatter being forced over the extension 39 until'the end thereof contacts the top 31. The condenser is also provided with an integral outlet tube received within the upper end of the flexible outlet tube Hi, the said end of the latter contacting the top 31 the same as the end of the tube l5.

The cooling water enters the condenser through the flexible tube I5 and conduit 38 and leaves the condenser through the conduit 40 and flexible tube IS. The conduit 38'extends almost to the bottom of the condenser so that the cooling fluid is introduced at a point in the condenser where it will bmosteffective, namely, adjacent the inlet port ii of the extraction tube; As the vapors strike the condenser and travel upward along the outside walls of the condenser, the same condense and fall to the bottom of the tube I! as previously explained.

The top of the condenser is of greater diameter than the mouth of the extraction tube andmerely rests on the peripheral lip of the latter, whereby the condenser can be quickly removed. Instead of providing a tight seal between the extraction tube and the condenser as has been done heretofore, we. prefer to provide a smallvent between the'tube I1 and the condenser. This is done in a very simple yet effective manner which is exaggerated somewhat in the drawings for the The-tube I! has one or more thereof so that a space is provided between the lip 41 and the top 31 of the condenser. The condenser is held in spaced relation to the inner wall of the extraction tube by means of the small nipples 43 arranged peripherally about the lower This permits the solportions thereof will be at a temperature which.

denser'so that the vapors are more effectively. con

claimed, and this also prevents the condenser from contactingthe insidebf the extraction tube to form an area 'onthe extraction tubewhich is cold enough to cause moisture to formon the .:outside thereon. The ends'of the small nipplesiare so small'that they'have verylittleeffecton the temperature of the walls of the extraction tube should the latter be contacted byi-th'enipples. Also sincerthe nipples are solid, the {outermost properly. Withoutthe vent, a partial vacuum'is 7 produced in the extraction flask whenwthe cooled I solventfrorn the" extraction tube siph'ons back into the hot extraction flask; Atmospheric pressure on the outside of the mercury inJ-the trough of the extraction flask thenis suiiicient to force part of themercury into the flask. ,This cannot occur if the pressure within the flask is approximately the same as thatoutside theflask. l'flherefore the vent'eliminates. this danger. I 3 Since the condenser is practically enclosed by the extractor exceptat the top, the temperature-20f the extraction tube is more nearly that of the room temperature thanis-the condenser and therefore there is no tendency-for the extraction tube to sweat. The upper side of the condenser is concave so that any moisturewhich condenses on the top will collect there and not run down over the sides of the extractoror into the same through the .joint between the condenser and extractor.

Aspreviously explained, the presence of moisture m the condenser is detrimental and we have avoided any, possibility of moisture getting into the extractor because of the condenser. If under conditions of extremely shigh humidityfimore g I removal. In ordinary types of flasks. where solvent accumulates, it does s'o-to a marked .d'egree moisture collects in the concave top of the condenser than the same will hold, it will overflow and .ithe'moisture willrun over and'drip off the tractorcould be made deeper than shown if desired, butexcept underextreme conditions, a depth. substantially that illustratedwill be sufficient. I

Since the tubes Hand [6 are relatively: thick, the ends thereof which contact theconc'ave top will cover up a considerable area. of thesame and thus reduce the amount of moisturewhich could form. Of course it is obvious that-this rubber tubing also prevents the sweating of the glass extension39and the glass outlet 40.

A glass ball 44 which is preferablycolored in or der that it may be seen readily, is arranged in the lower end. of the condensing tubefiii and when at rest is only slightly spaced from'the lower end of the conduit38. As the coolingfluid flows. out of the lower end of: this conduit, the ballis agitated by the same andthe amo'untof agitationdepends on the rate of. fiow of'the cooling: fluid. Therefore, the amountofagitation'indicates in a general way the amount :of cooling fluid flowing and the operator soon is ableto regulate the flow of cooling fluid even beforelthe heating of the solvent begins. L

:A wire loop 45, the ends 46 and 41 of which embrace and holdin position the portionsofithe tubes [Sand it which embrace the .extension 39 and the outlet conduit 40, not only helps to pl'- vent leakage by having its ends thusarranged,

but also serves as a meanswhereby the condenser may be supported when'not arrangedinthe extractor tube. Thus the loop maybe arranged .over the handle of thestop cock. whichiregu lates the flow of water through the condenser, bra separate hook may be providedbfortthis purpose; This relieves'the flexible-tube .Qf the weight ofv the condenser whenthelextrac-tion tube. is removedand makes it unnecessary to re+ move the tube l5. Thelowerend'ofjthefiexible outlet conduit I5 extends into the wastepipe 49 a distance sufiicient to avoid a total withdrawal of the same from the waste'lpipewhen the com denser has been raised and suspended from. the handle-of said stop cock by the wire l'oop..45.

Therefore, while the material inthe'extractor is being removed or placed therein, it is notlnecessary to. interrupt the actionof the condenser which the operator may have regulated toa nicety to'suit the requirements of the process. Thus successive operations of the apparatus-2110 notrequire re'regulationof the condensenai "While we do'not wish to limit ourselvest'to'the material used for our apparatus, wehave found that glass'is mostsatisfactoryand all the-parts with the exception of the parts l2, l4, l5, I6,.26, 34,45, 48 and 49 are made of glass. In other words the main parts of the apparatus,- namely, .the

flask, the extractor and the condenser: are=.all glass, thereby making it possible to clean-the same more readilyas well as prevent any chemi-' cal activity which'may. result irom the use of other-materials. y i Since the outer upper edge of the troughis lower than the lip on the flask, thereislittle 1 chance for mercury to spill into theflask'should the flask be jarred. By preventing theaccumu lation of solvent in the'trough there is no danger of spilling the same when the fiask-isjaried on sometimes. 'Ihissolvent collects in the spacebetween the neck of the flask and the outer skirt (the'only one now provideddn devices of this nature) and sometimes reaches the :top oiuthe flask. The mercury prevents the same from flowing past the lower edge of the skirt, 'but when the extraction tube israised,v the solventfiows rapidly over themeroury to-the outer'wallof thetrou'gh and will splash over/the same.' --'1By eliminatingthis in our invention'we have greatly reduced the fire hazard and rendered: thev iristru ment moreldesirable.

7 Having thus fully described our" invention,

invention pertains niaymake "various what we claimand. desire to secure byfLette'rs Patent of the-United States is: a. a 1. In a device of the class describedgthe combination with 'a' solvent receiving flaskhavingan open "mouth, of an extraction .1 unit havlngJ'a mouth, the lip-of which overlaps the lip of the mouth of said flask, a liquid receiving'troughar-v ranged about the overlapping lips of said flask and extraction unit and of suflicient size to. receive a sealing liquid to a depth .to seal the space between said lips so that the said flask andextraction'unit are in sealed communicationwith each other, and means for draining "the sealing-liquid from said trough while the parts are in their op-. erative positions with respect to each other; 7

.2. In a device of the class described, the'combination with a liquid receiving flask having an open mouth, and a sealing liquid receiving trough arranged circumferentially about saidmouth, of an extraction unit having a. mouth the. lip of which extends into said trough a distance suflicient to be entirely covered by the sealing liquid when the latter is placed in .said trough, said trough having, a drain opening therein for draining the liquid from said trough, and means for closing said opening.

3. In a device of the class described,;,the combination with a flask having an open mouth and a trough, U-shaped in cross-section and .arranged circumferentially about said mouth, said trough having a drain opening therein ata point near the bottom thereof, of means for closing said opening, and an extraction unit having an open. mouth, the edge of which, when said unit and flask are in operative relation with respect to each other, extends into said trough a suflicient distance to be immersed in the sealing liquid when the latter is placed in said trough.

4. A device as set forth in claim 3' in which the extraction unit is provided with a skirt contiguous with'the inner wall of said mouth and spaced therefrom, the said skirt extending into said mouth of said flask.

5. In a. device of the class described, the combination with a flask having an open mouth, of a trough arranged circumferentially about said mouth and contiguous with the outer wall of said flask for receiving a sealing liquid, an extraction unit having an inlet conduit for receiving vapors from said flask, and at least two skirts contiguous with said inlet conduit and arranged one within the other, the inner one of said skirts extending into the'mouth of said flask, and the outer one of said skirts extending into said trough when the extraction unit'is in operative relation with respect to said flask. 1

.6. A deviceas set forth in claim 5 in which said trough has a drain opening therein near the bottom thereof and in which there is provided a means for closing said opening when desired.

7. A flask of' the type described comprising a body portion having a mouth, a liquid receiving trough surrounding said, mouth having a drain opening therein, near the bottom thereof, and means for closing said drain opening.

8. A device of the class described comprising an extraction tube having an inletlconduit, .the lower endof which is provided with at least'two peripherally extending contiguous I .ski'rts one within the other, the said skirts being spaced to receive-the lip of an extraction flask, one of said skirts being adapted to be immersed in a liquid seal. 7

9. In a'device of the class described, the combination with a distilling chambergof an extraction chamber communicating, therewith and having an opening therein, a condenser cooperating with and removably supported within said opening, 'a pair of projecting conduits onsaid condenser, one conduit being-the. inlet conduit and the other the outlet conduit, a pair of separate flexible conduits, one of which has one end thereof embracing .one of said projecting conduits and theother of which has an end embracing the other projecting conduit, and a loop member, the opposite ends of which embrace the said ends of said flexible conduits to hold'the same firmly about their respective projecting conduits on said condenser, the said loop also acting as a means whereby the said condenser may be supported by suitable .means while out of operative arrangement within said extraction. chamber.

10. In a device of the class described the combination with an extractor tube having an opening in the upper. side thereof, of a condenser freely supported within. said extraction tube through said opening and extending a substantial distance into said tube, a head on said condenser resting on the edge'.of=said opening, the outer periphery of the condenser which lies within said tube being of a smaller outside diameter than the inner diameter of ,said tube, and means arranged between said condenser and tube for spacing the outer walls of said'condenser from the inner wall of said tube. I I '11. In a device of the class described, the combination with an extraction charhber'having an opening in an upper wall thereof, a condenser cooperating with .andremovably supported within said extraction chamber and extending downwardly into the same through said opening,'the condenser having an enlarged head on the upper side thereof the under sideof which engages the edge of said opening in said wall, whereby the condenser is supported in operative. position within, said chamber, said enlarged head having the upper outer side thereof formed with a depression extending substantially to the outer edgeof said headfor collecting any moisture formingon the upper side of said head to thus prevent the same from running over the outer edge of the head and along the. sides thereof into the extraction chamber.

12. A condenserfor extraction apparatus and the like comprising a body adapted to be arranged within an extraction chamber andextend through an opening in the upper side thereof, and a head on said condenser adapted to project outside said extraction chamber and having a downwardly extending lip on the periphery thereof of a size to extend'beyond the outer supporting edge of said opening in said extraction chamber, whereby moisture forming on the upper side of said head will drain oif the same free of the condenser body and the joint formed by the meeting portions of .said condenser and said edge of said opening, whereby when the condenser is placed in said extraction chamber with the head protruding above saidextraction chamber any moisture dripping from the lip will not flow along the sides of ;the condenser intothe extraction chamber through the aforesaid joint.

13. A device of the class described comprising a condenser body having a transparent portion, an inlet tube leading into'said body, the inner side of said body near said inlet tube having a depression, a freely supported movable element in said depression in the path of cooling fluid enrate of flow of said cooling fluid through said condenser.

14. In a condenser of the class described, the combination with a tubular body adapted to be arranged with its longitudinal axis vertical when w the same is in use-said tubular body having a closed lower endhaving an inner upwardly forcing concave surface thereon, an inlet tube ex tending down into said body to a point-closely adjacent said bottom, near the lowest point on said concave surface, a'freely movable ball rest ing on said concave surface and gravitating toward said lowest point thereon, the end of said tube being spaced sufiiciently from said concave surface" to permit said ball to occupy the space therebetween.

15. A condenser of the class described com'' prising an elongated body portion having a laterally extending shoulder near the upper end thereof adapted to rest on the edge of an opention with an extraction tube having an opening in the upper side thereof of a condenser removably arranged within said tube and extending through said opening, a head on said condenser freely resting on the edge of said openingto support said condenser'withinsaid tube, the edge of said opening and adjacent'portion on said head being so formed that they are separated at least at one point to permit vapors to escape from said extraction chamber. I

17. In a device of the class described, the combination with an extractor having an opening therein, a condenser extending into said extractor and having a laterally projecting means thereon adapted to engage the edge of said opening and support the condenser in operative position, in-

let and outlet conduits for said condenser and a drain tube into which the free end of said outlet conduit extends, said outlet conduit being of a length to extend into said drain tube a sufiicient distance to prevent total withdrawal of same from said tube upon total withdrawal of said condenser from said extractor, whereby the flow of cooling fluid through said condenser may be continued even when not supported within said condenser.

CHARLES RASCHER. MAX F. BETZOLD; 

